The main objective of this research is to understand better how the cell works in terms of its organelles and membranes. We are developing cell fractionation procedures to separate all of the membranous subcellular organelles from the same homogenate. This procedure will pave the way for the study of dynamics of cell function. Although lipid is known to be an essential component of membranes, its exact role and the molecular basis of its action remains obsure. In this regard, beta- hydroxybutyric dehydrogenase, a specific lipid-requiring enzyme is being studied to elucidate the basis for its lipid requirement for function. We are studying sarcoplasmic reticulum in terms of membrane dissociation and reconstitution in order to learn how one membrane works and is assembled. Other fundamental problems of membrane structure and function which this research hopes to clarify are the role of lipid in permeability properties of membranes, the biogenesis of membranes, the comparative biochemistry of membranes from different sources as well as the factors involved in the re-assembly of functional membranes from lipid and protein components. A many-faceted approach to the study of the structure and function of membranes is necessary because of the complexity of the subject and our still rudimentary knowledge of the mechanism of action of membranes. We hope to apply some of the knowledge gained from these studies to medical problems. Samples from autopsy or biopsy are usually not studied with regard to lesions referable to subcellular organelles since such studies require extensive preparations and timing. For this purpose we are developing technology for storage of tissue which would allow cell fractionation at a later time.